US 11,680,159 B2
Polyolefin-based microporous films via sequential cold and hot stretching of unannealed polypropylene copolymer films
Wenyi Huang, Midland, MI (US); Mark Alan Barger, Midland, MI (US); Gary D. Parsons, Midland, MI (US); and Ioannis V. Bletsos, Midlothian, VA (US)
Assigned to DDP SPECIALTY ELECTRONIC MATERIALS US, LLC, Wilmington, DE (US)
Filed by DDP SPECIALTY ELECTRONIC MATERIALS US, LLC, Wilmington, DE (US)
Filed on Sep. 16, 2020, as Appl. No. 17/22,290.
Claims priority of provisional application 62/908,146, filed on Sep. 30, 2019.
Prior Publication US 2021/0095110 A1, Apr. 1, 2021
Int. Cl. C08L 23/16 (2006.01); C08F 210/16 (2006.01); C08L 23/12 (2006.01); C08L 53/00 (2006.01); B29D 7/01 (2006.01); B29D 99/00 (2010.01); B29C 55/00 (2006.01); B29C 55/04 (2006.01); B29L 31/00 (2006.01); B29K 23/00 (2006.01)
CPC C08L 23/16 (2013.01) [B29C 55/005 (2013.01); B29C 55/04 (2013.01); B29D 7/01 (2013.01); B29D 99/005 (2013.01); C08L 23/12 (2013.01); C08L 53/00 (2013.01); B29K 2023/12 (2013.01); B29K 2023/16 (2013.01); B29L 2031/712 (2013.01); C08F 210/16 (2013.01); C08L 2203/02 (2013.01); C08L 2203/162 (2013.01); C08L 2203/30 (2013.01)] 28 Claims
OG exemplary drawing
 
1. A microporous polymer film comprising:
one or more polypropylene copolymer, said one or more polypropylene copolymer comprising one or more polypropylene homopolymer chain segments and one or more ethylene-containing copolymer chain segments;
and wherein the microporous polymer film comprises:
(i) one or more polypropylene homopolymer chain segments in total amount of from 50-82 wt %, based on a weight of the microporous polymer film, or from 43-79 mole %, based on a mole content of polymerized units of propylene in the one or more polypropylene homopolymer chain segments as a percentage of a total mole content of polymerized monomer units in the microporous polymer film; and
(ii) one or more ethylene-containing copolymer chain segments in total amount of from 18-50 wt %, based on a weight of the microporous polymer film, or from 21-57 mole %, based on a mole content of polymerized monomer units in the one or more ethylene-containing copolymer chain segments as a percentage of a total mole content of polymerized monomer units in the microporous polymer film; wherein at least a portion of the one or more ethylene-containing copolymer chain segments comprises polymerized units of ethylene in an amount of at least 45 wt %, based on a weight of the one or more ethylene-containing copolymer chain segments, or at least 55 mole % based on a mole content of polymerized units of ethylene in the one or more ethylene-containing copolymer chain segments as a percentage of a total mole content of polymerized monomer units in the one or more ethylene-containing copolymer chain segments.